Download Data Mining in Atmospheric Gravity Waves

Data Mining in Atmospheric Gravity Waves Alfred Ultsch1,2, Christopher Rogos2 and Christof Maul2,3 1
Databionics Research Group, University of Marburg, Marburg, Germany, [email protected]‐marburg.de 2
Science Division, Academical Fyling (AKAfly), University of Frankfurt, Frankfurt, Germany. 3
Institute for Physical and Theoretical Chemisty, Technical University of Braunschweig, Braunschweig, Germany. Gravity waves can emerge as a result of the perturbation of atmospheric ciculatory systems [1]. They encompass periodic, yet geographically stationary, changes in temperature, pressure and vertical wind components. Occurrence of such waves is frequent if strong winds hit high mountains [2]. Secondary effect of such waves may also be encountered as clear air turbulence (CAT) in commercial flights. Atmospheric gravity waves strongly influence weather phenomena and on a larger time scale climatic processes. They are responsible for the vertical mixing of the atmosphere from the mesosphere up to the stratosphere [2]. First results from research flights in the Pyrenees during the spring 2015 measuring campaign are reported. Several flights with a sensor equipped unpowered glider in altitudes between 2000 and 7000m were undertaken. Data Mining and Knowledge Discovery methods from the Databionics Lab in Marburg were applied [3]. The results point to so far new and interesting patterns in the structure and formation of lee waves. These findings are compared with results from other measuring campaigns [4,5]. [1] Achatz, U., R. Klein, F. Senf: Gravity waves, scale asymptotics and the pseudo‐incompressible equations. J. Fluid Mech. 663: 120 – 147, 2010 [2] Placke, M., P. Hoffmann, M. Gerding, E. Becker. M. Rapp: Testing linear gravity wave theory with simultaneous wind and temperature data from the mesosphere. J. Atmos. Sol.‐
Terr. Phys. 93: 57 – 69, 2013. [3] Ultsch, A.: Swarm Data Mining for the Fine Structure of Thermals, Technical Soaring, Vol. 36, Nr. 4, pp. 37 ‐ 44, 2013. [4] Stromberg,I. M., Mill, C. S., Choularton, T. W. and Gallagher, M. W.: A case study of stably stratified airflow over the pennines using an instrumented glider, Boundary‐Layer Meteorology, Volume 46, Numbers 1‐2, pp 153‐168, Springer, Netherlands, 1989 [5] Millane,R., Brown,P., Richard,G., Enevoldson,E., Murray,J.E.: Estimating mountain wave windspeeds from sailplane flight data, Proceedings of SPIE ‐ The International Society for Optical Engineering, E01, pp104‐109, 2004.